Carburetor



Dec. 22, 1936. G, Kor-PE CARBURETOR Filed April 13, 1935 2 Sheets-Sheet 1 ATTORNEY l Dec. 22, 1936. arKoPPE cARBUREToR Filed April 1s, 1955 2 Shee'cs--Shee'rI 2 ATTORNEY atented Dec. 22, 1936 turno ST-'TfEs cAnBUnEron s Georg Koppe, Prague, Czechoslovakia,

Application April 13, i935, serai No; rane In Czechoslovakia April 2li, 1931i i 9 Claims.

which the fuel thus atomized may be mixed uniormiy and 'free of eddies with the mainair being also adjustable as to its quantity.

A further object of the invention is the provision of a carburetor adapted to furnish a correct ratio of the mixture of air and `fuel for any condition of operation (load condition) of the motor and for any kind of fuel.

'The essence of the invention consists in an auxiliary air funnel being arranged coaxially with the fuel nozzle and having its inner surface 'so shaped, that the ring space formed between the .'fuel nozzle nd the inner surface of the auxiliary air funnel ecreases in the direction of the air How to a substantially ring-shaped slot located near the discharge openings of the fuel nozzle, y

and-permitting only such quantity of air to pass as is necessary for the atomization of the fuel, the size of the slotbeing adjustable by an axial adjustment of the auxiliary air funnel with respeci; to the fuel nozzle. The invention furthermore consists in means for adjusting and xing.

the fuel nozzle together with the auxiliary air funnel in the direction of the main air funnel wherein the latter, consisting of 'elastic members, is exand consisting of elastic material, which capillary body divides the fuel column flowing through the center bore of the nozzle into small columns which, when leaving the fuel nozzle, are severed into finest particles by the atomizng air coming from the slot between thefuel nozzle and the auxiliary air funnel, and are uniformly mixed therewith.

The atomized iuel comes together with the (ci. tenis) l Vmain air flowing through the ring space between the auxiliary air funnel and the main air funnel, and is furthermore divided yby the :nain air due to its energy of flow, and intimately mixed therewith. f 5 'Ihe invention furthermore consists in a main air funnel comprising elastic mexbers connected at their ends to form at least two-hollow bodies or jackets lying close to each other and consisting of elastic material. By suitably choosing thematerials, such an expansionv or contraction of the main air funnel by the prevailing motor Vacuunr may be accomplished under any condition of operation of the motor, that the' quantity of the main air flowing through the main air funnel, is adequate to the quantita;r of fuel discharged from the fuel nozzle so that the correct ratio of the mixture of air and fuel may be obtained under any condition of operation. i

For the starting and the idlingof the motor, a mixture of a light fuel with air maybe used which.` may becreated in a separate carburetor device. Further objects, advantages and details will be apparent from the following description and the drawings illustrating embodiments of my in- Fig. 2 of a carburetor as per the invention with the fuel nozzle and the air funnel.

Fig. 2 a top view, partly in section along line B--B of Fig. l showing the organ for regulating the light fuel. g

Fig. 3 a horizontal cross section along line C-C l of Fig. 1 on a larger scale, showing the main air funnel, (at the left hand side the smallest, and at the right hand side an enlarged passage).

Fig. 4 a cross section alongline D-Doi Fig.

l, showing the' wick arrangement.

Fig. 5 an axial cross section of the top of the 40 fuel nozzle illustrated in l, on a larger scale.

Fig. 6 an elevation of the top of the fuel nozzle.

Fig. 'l a longitudinal section of the top of another fuel nozzle with the auxiliary air funnel, the form of the inside surface oi' the main air 45 funnel being only indicated.

Fig. 8 an elevation oi the fuel. nozzle as per Fig. 7 on a larger scale.

Fig. 9 an elevation of the fuel cone or the regulating organ shown in l, and oi its groove 5@ on a larger scale.

Fig. 10 a side View of another carburetor with 'an adjustable neat chamber for heavy fuel on a smaller scale, and Y f Fig. l1 a side View' or another carburetor in which only one kind of fuel is used, and whichl has only one float chamber.

On the float chamber I for heavy fuel, the iioat chamber 2 for light fuel, for instance gasoline, is mounted, for instance by means of screws. The inlet of the gasoline supplied from the tank (not shown) through pipe v2 is controlled by means of the float device p2 with a needle of wellknown construction, the latter not being shown. A chamber 5 is fastened with one of its ends on top of chamber 2. Its other end forms the casing for the control member 1, and is tightly screwed to chamber 3 of throttle k. In chamber `5 a flat tube 8, for instance of the shape illustrated in Fig. 4, is provided, consisting of wire net work, perforated sheet metal, or the like. Tube 8 is enclosed over its entire length by a wick 9 of any suitable make which dips into the gasoline of chamber 2 with a sufficiently long portion.

Tube 8 reaches with one end into the air space of float chamber 2. Openings o are provided in the wick at this end and allow air to enter-into the interior of the tube. The o er end of tube 8 opens into the aperture 34 lea ng to cone 1 of the control member. The cross section of aperture 34 equals that of tube 8.

Cone 1 has a longitudinal hole 35 so formed, that it still remains in connection with aperture 34 when cone 1 is turned a certain angle. Hole 35 opens into an especially formed recess of cone 1 (see Fig. 9). Auxiliary air can flow through bore 351 in cone 1. The quantity of this auxiliary air may be adjusted by means of a wellknown screw valve which is screwed into the casing in a manner that it is adjustable, and may be kept'in its adjusted position.

Cone 1 has a prolongation of smaller diameter to which lever 39 is fastened which` may be controlled from the drlvers seat also while the motor is running. A stuffing box 31 with nu and gasket of wellknown construction prevents "wrong airI from entering the interior of the con`e casing.

Interiorly, regarding the' longitudinal extension of recess 36, a certain number of small bores are arranged in the flange of the chamber 5, said flange being fastened to the throttle chamber f3. Bores 38 correspond to the calibrated bores 38' provided in chamber 3.

By means of control member 1, the quantity and partly also the quality of the mixture of gasoline and airis adjustable, and by means of the screw valve the quality of the mixture is adjustable.

In the top of fuel nozzle III a body 45 in cushion form is arranged' made of a capillary mate\ rial, for instance of sponge, animal hair, very ne steel wool or the like. In the embodiment. of

Figs. land 5, this body is held by means of the screw cap |81 provided with large openings 48 and a 'central bore 48. The position of this cap in relation to the nozzle body III is determined by space I2 it flows through a fine bore I3 to the capillary body 45. The flow of the fuel to the top of the nozzle may be controlled 'and closed by means of needle 21 at the mouth of bore I3. Needle 21 is screwed into the nozzle by means of the threads 28. A downward outflow of the fuel is prevented by a stuffing box consisting of a ring Il, a gasket 20, and a. nut 2| the position of which tened the lower surface of which is provided with fine radial teeth 30. 'I'hese teeth are engaged by [similarly formed teeth of levier '3I which is pressed against disc 29.by means of nut 32 and may be operated at B by means of a well known Bowden cable.

Nozzle I0 with its cylindrical portion I1 of larger diameter is mounted in the bracket I1 fastened to chamber I. A nut 25 is screwed into this bracket and abuts on the one side against the recessed front surface of the enlarged portion I1 of nozzle I0, and on the other side against the bipartite ring 24 inserted in a ring groove of the nozzle and secured by well known means against falling out. The point of the screw 26 screwed into bracket I1 reaches into the longitudinal groove I8 of the lower enlarged portion I1 of the nozzle. By turning nut 25 nozzle III may be adjusted with relation to its height and is prevented from turning by screw 26. The moving of the nozzle is made possible by the yieldinglinesss of the inlet tube r. The adjustment of needle 21 controlling the fuel inlet re-A Another embodiment of the fuel nozzle is illus- 4 matic unscrewing by a check nut 41. s

Tube 46 projects into the fuel space I2 of nozzle III and protrudes almost down to the bottom of this space. The' lower mouth cross section of the longitudinal bore of tube 46 is adjustableby needle 21 described above. Instead of needle 21, however, a similar valve, may be f arranged at any suitable other-,part of the fuel inlet pipe r leading to nozzle III as shown for instance in Fig. 10 where a needle valve device 21', 28 3|', and B' is provided in connection with the fuel pipe r leading from the oat chamber towards 'the nozzle system within chamber 3.

The highest point of space I2 of nozzle I0 is connected with the air space surrounding nozzle I0, mainly, however, with a ring space between the outer surface of the nozzle top and the inner surface of the auxiliary air funnel 23by means of a bore or of a plurality of bores in order to allow ar to enter and to escape.

Ihe arrangement of space I2oifers a further advantage inasmuch as, at a sudden acceleration of the motor, a fuel storage is being kept in it to serve at the time when the fuel column in the inlet pipe leading to the nozzle becomes accelerated to the desired extent, in a manner that the motor may be accelerated without any disturbance. I l

The top of nozzle I8 is surrounded by the auxiliary air funnel 23 which is connected by means of narrow ribs 232 with a funnel hub 231 screwed on the nozzle I0. As apparent in Fig. 7, funnel 23 may. be axially moved with relation to the nozzle top in a manner that the ring shaped cross section 52 for the air passage between the outside surface of nozzle III and the inner surface of funnel 23. may be adjusted. A check nut 5I secures the adjusted position of the funnel it.

The outside surface of the funnel 23 reaching into 'the cross section of the passage through the Venturi shaped main air funnel T is so formed that the cross sections of the ow along this surface, that means between thisv surface and the inner surface of the main air funnel T uniformly decrease towards the end of funnel 23, for instance from cross section V53 to the cross section 531. 'Ihe speed of the air sucked in by the 'motor and flowing in the direction of arrow S2, will thus become uniformly increased.

The -main air funnel 'I' is so formed, that the crosssection of the air ow is changeable according to the motor vacuum. An embodiment of this device is shown in Figs. 1 and 3. The funnel consists of two jackets Z1 and l2 of elastic material, one arranged within the other, and both provided with longitudinal slots s. slots sl start from the upper end downward Without, however, reaching to the lower end. They end in bores b so that the jackets are kept together at this place. The jackets are so placed respecting each other, that each jacket covers the longitudinal slots sand the bores b of the other jacket respectively. The lower ends of both jackets are`connected with each other in any suitable manner for instance byibeading,

riveting and the like, and they are held for i`n stance by means of a slotted spring ring 42 engaging a ring groove of chamber 3. The upper end of funnel T elastically contacts ,the bore of the throttle chamber 3.

If the vacuum in the motor suction pipe exceeds other suitable manner provided it is capable of automatically altering its shape and particularly its width in the'desired manner in response to a change'of the motor vacuum.

Different fue]A levels will adjust themselves in nozzle ld if different fuels but the same oat p1 are used. This may have the disadvantage that losses of fuel may occur through the dripping of n order to prevent this according to the inventio the float chamber L1 is so arranged that it may be' moved parallel to the longitudinal axis of nozzle lll in a dove-tail groove of' the carburetor chamber 3. It may be adjusted in a desired position according to a scale 56 to be seen from `the outside. This is schematically shown in Fig. lll. In this case float chamber i for the light fuel is not connected with chamber il. l

' the carburetor as per the invention operates in the following manner:

1 The gasoline rises up through wick tl which is dipped into it and permanently saturated due to the wellknown wick eff-ect. IfV the cone .il has the position shown in Figs. l and 2 at the starting of the motor, then the motor sucks in air which flows through pipe i3, apertures til and 35 and through the bores 313 and M1. While passing along the interior surface of pipe d, the air takes along gasoline from the gasoline saturated wick in such a manner that a corresponding starting mixture will be formed. The amount of the mixture streaming into the motor may be regulated by adjusting cone fl, the longitudinal groovel tt The main air funnel may be made also in any .unknown extent.

responding dimensioning of pipe 8,-several pipes 5 arranged' in any suitable manner with respect to :each other may be used alsof-Land by the choice of a suitable wick, the necessary quantity of mixture for the starting and idling is secured. During the idling the throttle is closed, and separates consequently the motor suction pipe entirely from the chamber of thel main fuel nozzle.

The startingi mixture may be made richer or poorer by screwing screw valve 55 in or out, respectively.

When the motor isrsufciently warmed up during the idling, that a condensation of the heavy fuel may not occur any more so easily, and if the throttle is then opened a little, air from the nozzle space flows into the suction 'pipe whereby the air current passing along the apertures 381, causes an increased suction of a saturated mixture of light fuel and air due to its energy of,4 flow. Consequently, the number of revolutions of the motor becomes increased. Due to the inowing air, however, the mixture ratio of the light mixture comes closer to normal whereby a further increase of the number of revolutions takes place which in turn increases the vacuum at the nozzle luso much, that the heavy fuel be-V gins to atomize, while the light fuel carburetor is still operating. In the course of the further opening of the throttle, the throttle edge moves, more and more away from the wall of the cham bei' 3 whereby the effect of the energy of flow of the mixture current coming from the space of the nozzle Il), decreases again. The change from the operation with light'fuel to that with heavy fuel consequently takes place automatically without intermission or disturbance.

By the vacuum at the throttle lil, fuel is sucked in through the bore i3 respectively the little tube d6, land iiows through the body i5 whereby the fuel is divided in as many partial columns as the body has capillaries. The vfuel particles pass through the nozzle openings i8 and 491 or d@ into the air current coming from the. slot 52 whereby it is furthermore divided and thoroughly mixed withthis air.

Since the size of the capillary may be made correspondingly small, (by compressing body mit of yielding material with the help of the little tube llt and the cap Illll respectively) a rate of' atomization of the fuel will be obtained toa hitherto By moving the auxiliary air funnel 23 towards the top of nozzle It the 4size of slot 52 and hence the amount and the speed of the atomizing air may be adjusted whereby best atomization of a fuel of any kind is obtained.

By axially moving nozzle ld andV funnel 23 together, the size of the cross section 531 and thus the quantity of main air owing into the motor may be adjusted. Due tothe uniform contractionof the cross sections b3 and i531,l the air flow is free of eddies. Y The energy of flow of the air flowing out at 53.1, causes a thorough mixture of thev same with, the 'saturated atomizing mixture coming from the top of the nozzle.

The adjustment of the auxiliary air funnel 23 as regards to nozzle it and of this group as to funnel T is Very simple since the vmotor directly responds with a change of its number of revolutions to a change of position of the funnel 23 and nozzle lill in a manner-that the number of A If, with the carburetor according to 4the in-V y vention, the best adjustment for the atomization and for the correct mixture ratio of the main air `and the atomizing mixture for any fuel has been made, a correct mixture ratio of air and fuel will be automatically obtained for all conditions of operation if the funnel T is used which expands and contracts depending upon the vacuum and hence upon the motor output, the material of which is so chosen that the air passage of the funnel T changes in a denite ratio to the vacuum. In this manner the most favorable conditions for an utmost of utilization of fuel are created by the carburetor according to the invention which considerably saves fuel and renders a higher motor output.

On account of the above mentioned excellent atomiza-tion of the fuel, the necessary preheating of the mixture in order to prevent a. condensation will be much smaller than with the construction hitherto known, if not eliminated entirely. On account of the smaller heating of the mixture, the mixture weight sucked in by the motor, will be larger and consequently, the motor emciency will be higher, or the lesser eiliciency hitherto observed, will disappear.

The carburetor according to the invention may also be used for'light fuel operation only, and this at a considerable saving of fuel and at a gain of a higher output. In this case, the oat chambers I andl 2 may be united to a single one as schematically illustrated in Fig. 11. The wick carburetor 8, 9 shown in dashed lines, leads the fuel mixture behind the throttle t and the idling will be adjusted by the cock 1 as described. The

other parts are constructed as described.

'Ihe capillary bodyA 45 may be shaped in a suitable manner, for instance ring-shaped etc., and the nozzle used together with it, may also be employed in kmotors with self ignition' and coaxially, said needle valve within said nozzle,v

with spraying of fuel under pressure. 'I'his nozzle may also be used for instance with oil furnaces.

I claimz- 1. In a carburetor the combinationof an elastic main air'funnel, adapted to alter its width under the influence of a motor vacuum, an auxiliary air funnel, a fuel discharge nozzle, a needle valve, said main air funnel, said auxiliary air funnel, said nozzle and said needle valve being arranged said nozzle within said auxiliary air funnel and said auxiliary air funnel within said main air funnel, means for controlling the position of said needle valve within said nozzle for adjusting the passage of the fuel through said nozzle, means for adapting the position of saidauxiliary air funnel in relation to said nozzle without interfering with the position of said needle valve in respect to said nozzle, and means for adjusting 'the position of said nozzle with said auxiliary air funnel inrelation tothe main air funnel. 2. In a carburetor the combination of an elastic main air funnel adapted to alter its width under the inuence of a motor vacuum, an auxiliary air funnel, a fuel discharge nozzle, said main funnel, said auxiliary air funnel and said nozzle being arranged co-axially with the auxiliary air funnel between the main air funnel and the nozzle, said main air funnel having alower portion tapering towards the top, said auxiliary air funnel having a wall thicker near its top ,than near its lower end and said nozzle having a tapering top, whereby ring spaces gradually decreasing in Width towards the narrowest portion of said main air funnel are formed, means for adjusting the position of said auxiliary air funnel as to its height with respect to said nozzle, and means for adjusting the position of said nozzle with said auxiliary air funnel as to its height with respect to the narrowest portion of said air funnel.

3. In a carburetor having a casing,l a self-adjusting main air funnel of Venturi shape comprising two jackets of elastic material each jacket being provided with bores near its lower end and with longitudinal slots extending from the top of the jacket, and ending in said bores, said jacketsy being arranged close to and within one another, each slot of the one jacket being covered by a portion betweenrtwo slots ofthe other one. said jackets beingconnected with each other at their lower ends, the lower end of the funnel .being fixed within the carburetor casing and the upper end being free to slide therein, whereby the funnel is adapted to alter its -width in response to a vacuum prevailing in the upper portion of the casing.

4. A carburetor comprising a casing, a main air funnel of Venturi shape, and an auxiliary air funnel, said main air funnel consisting of two vided with bores near its lower end and with 1ongitudinal slots extending from the top of the jacket and ending in said bores, said jackets being arranged close to and within one another, each slot of the one jacket being covered by a portion between two slots of the other one, said jackets being connected with each other at their lower ends, the lower end of the main air funnel being fixed within the carburetor casing and the upper end being free to slide therein', said auxiliary air funnel being tapered towards its upper end and being arranged coaxially with said main air funnel and within its lower portion, and means for altering the position of said auxiliary air funnelV as to its heights-in relation to said main.

air funnel whereby a` ring space gradually decreasing in width towards` the top is formed, which -is changeable depending upon the adjustment of the auxiliary air funnel and upon the width of the main air funnel being changeable in response/to a vacuum prevailing in the upper portion of the casing.

air funnel having a hollow cone-shaped portion,

an interiorly threaded hub and ribs connected with said cone-shaped portion and said IJhub, said nozzle having a Acone-shaped top and an exteriorly threaded body portion there below,

threaded hub on said threaded nozzle body so as Ato be adjustable as to its height with respect to4 said nozzle, and means for adjusting said nozzle with said auxiliary air funnel as toits height in relation to said main air funnel.

j 6. A carburetor comprising a casing, a bracket in the interior of said casing, an adjustable main air funnel, a nozzle body mounted on said bracket in alignment with the axis of the main air funnel said nozzle body being provided with a central bore as a passage for fuel and having an upper threaded portion, a hollow top cap adapted to be threaded upon the upper portion `of said nozzle body, said top cap being provided with a central 'aperture and with lateral apertures, a capillary elastic bodywithin said cap so arranged as to be compressed depending upon the distance said cap is screwed d own on said nozzle body, an auxiliary air funnel mounted on said nozzle body and being adjustable as to its height in relation thereto, means for adjusting the height of said nozzle body m relation tosaid bracket, and means for arresting said nozzle body in its adjusted position. t

7. A carburetor as'claimed in claim 6 in which the nozzle body is provided with a lateral pas- 'sage communicating with -said central passage,

further comprising a flexible tube connected to said nozzle body for admitting fuel through the lateral passage to the central passage.

8. In a carburetor having a main air funnel, a fuel nozzle device comprising a bracket having an enlarged portion with a bore in axial alignment with said main air funnel, a nozzle body being inserted in the bore of said bracket and provided .with a central bore as a fuel passage, means for adjustably altering the position of said nozzle body as to its height in relation to said bracket,

o means in connection with said vbracket for arresting the vnozzle body in its adjusted position, an adjustable needle valve with a shaft within said nozzle body for closing its center bore,l said valve shaft protruding from said nozzle body. means attached to said valve shaft for controlling said needle valve, a cap with discharge apertures `on top of said nozzle body, a capillary body within said cap in the path of the uid passing through the nozzle bodyvto the discharge apertures of said cap, an auxiliary air funnel mounted on said nozzle body with its top near the discharge apertures of 4said nozzle cap, said auxiliary air funnel being so arranged as to leave, between said auxiliary air funnel and said nozzle cap, a substantiallyring shaped space decreasing in width towards the top, means for adjusting the position of the auxiliary air funnel as to its height in relation to the nozzle cap, and

- means for admitting fuel to the interior of said nozzle body.

9. A carburetor comprising an elastic main air funnel adapted to alter its width in response to a motor vacuum, a discharge nozzle, being adjustable as to its height in relation to said main air funnel and being provided at its top `portion with an adjustably compressible capillary body, an auxiliary air funnel, said auxiliary air funnel surrounding the top portion of said discharge nozzle and being in alignment with the axis o1' the main air funnel, said auxiliary air funnel being adjustable as to its height in relation to said nozzle, and said nozzle with said auxiliary air funnel being adjustable as to their height in relation to the narrowest portion of said main air funnel, a 

